The ACQUITY Premier Protein BEH C4 300 Å columns are QC tested with the MassPREP Protein Mix Standard and are optimized to separate proteins based on size, hydrophobicity and isoelectric point. If you compare to traditional C18 phases, the C4 ligand is less retentive and will minimize protein carryover, increase protein recovery, and improve peak capacity. This column is part of the MaxPeak Premier Class of Columns, which deliver the chromatographic performance expected from our particle technologies while increasing reproducibility, peak shape, and recovery for metal-sensitive analytes.  Note:  The column includes, at no additional cost, a vial of Waters MassPREP Protein Mix Standard (p/n: 186004900).